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captainFlint

Are the fragments that are generated made of up small squares as shown in the slide? If so, why? Wouldn't using triangles offer better accuracy for rendering an image?

Khryl

@captianFlint, the little square is just a representation. A fragment corresponds to a pixel in the image, and it will be rendered as the pixel after passing some tests such as depth test and alpha blending. so I guess the main reason for fragments to be little squares is that we like to represent image pixels as little squares, which is not a very precise representation ;-)

MaxFlowMinCut

;-)

jaguar

What sort of things can be primitives outside of the examples given (triangles, points, and lines)? Can any polygon be a primitive?

Khryl

@jaguar, yes, GL_POLYGON can be taken as parameter for gl_Begin(). Also you can consider quadrilaterals as primitives as implied by GL_QUAD.

dhua

@jaguar

There are also some really exotic primitives like GL_LINE_LOOP and GL_TRIANGLE_FAN. Here is a nice illustration:

In practice, triangles are used most often, though some subdivision algorithms use quads.